Methyl esters comprise any of a group of fatty esters derived from coconut and other vegetable oils, tallow, and the like. These compounds contain alkyl groups ranging from C.sub.8 -C.sub.18 in varying percentages, i.e., having varying carbon chain length distributions.
Methyl esters are used in a variety of commercial and industrial applications. Examples of application include their use in metal degreasing, paint stripping and graffiti removal as well as lubricants in the production of metals, i.e., in metal-cutting fluids, high-temperature grinding of metals, and the cold-rolling of steel. Additional applications include their use in lacquers, paints and varnishes, plasticizers and the formation of polymeric materials.
While the majority of commercially used methyl esters are formed synthetically by the reaction of methanol with an organic C.sub.8 -C.sub.18 acid in the presence of a catalyst such as sulfuric acid or p-toluenesulfonic acid, they also are known to occur in nature. Recovery of naturally occurring methyl esters may be accomplished by steam distillation, extraction or pressing, or by a combination of these processes.
In order to effectively utilize the favorable physical and chemical properties of methyl esters, it is often times necessary to emulsify them into a disperse, homogeneous form. Typical emulsifiers for methyl esters involve ingredients which contain volatile organic compounds. Examples of volatile organic compounds generally employed as emulsifiers for methyl esters include cosurfactants such as C.sub.3 -C.sub.5 alcohols and glycol ethers. Due to recent ecotoxicological awareness, the use of volatile organic compounds is undesirable.